src/librustc_codegen_llvm/lib.rs

   1 //! The Rust compiler.
   2 //!
   3 //! # Note
   4 //!
   5 //! This API is completely unstable and subject to change.
   6
   7 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/")]
   8 #![feature(bool_to_option)]
   9 #![feature(const_cstr_unchecked)]
  10 #![feature(crate_visibility_modifier)]
  11 #![feature(extern_types)]
  12 #![feature(in_band_lifetimes)]
  13 #![feature(nll)]
  14 #![feature(trusted_len)]
  15 #![recursion_limit = "256"]
  16
  17 use back::write::{create_informational_target_machine, create_target_machine};
  18 use rustc_span::symbol::Symbol;
  19
  20 pub use llvm_util::target_features;
  21 use rustc::dep_graph::WorkProduct;
  22 use rustc_ast::expand::allocator::AllocatorKind;
  23 use rustc_codegen_ssa::back::lto::{LtoModuleCodegen, SerializedModule, ThinModule};
  24 use rustc_codegen_ssa::back::write::{CodegenContext, FatLTOInput, ModuleConfig};
  25 use rustc_codegen_ssa::traits::*;
  26 use rustc_codegen_ssa::{CodegenResults, CompiledModule};
  27 use rustc_errors::{FatalError, Handler};
  28 use std::any::Any;
  29 use std::ffi::CStr;
  30 use std::fs;
  31 use std::sync::Arc;
  32
  33 use rustc::dep_graph::DepGraph;
  34 use rustc::middle::cstore::{EncodedMetadata, MetadataLoaderDyn};
  35 use rustc::session::config::{self, OptLevel, OutputFilenames, PrintRequest};
  36 use rustc::session::Session;
  37 use rustc::ty::{self, TyCtxt};
  38 use rustc::util::common::ErrorReported;
  39 use rustc_codegen_ssa::ModuleCodegen;
  40 use rustc_codegen_utils::codegen_backend::CodegenBackend;
  41 use rustc_serialize::json;
  42
  43 mod back {
  44     pub mod archive;
  45     pub mod bytecode;
  46     pub mod lto;
  47     mod profiling;
  48     pub mod write;
  49 }
  50
  51 mod abi;
  52 mod allocator;
  53 mod asm;
  54 mod attributes;
  55 mod base;
  56 mod builder;
  57 mod callee;
  58 mod common;
  59 mod consts;
  60 mod context;
  61 mod debuginfo;
  62 mod declare;
  63 mod intrinsic;
  64
  65 // The following is a work around that replaces `pub mod llvm;` and that fixes issue 53912.
  66 #[path = "llvm/mod.rs"]
  67 mod llvm_;
  68 pub mod llvm {
  69     pub use super::llvm_::*;
  70 }
  71
  72 mod llvm_util;
  73 mod metadata;
  74 mod mono_item;
  75 mod type_;
  76 mod type_of;
  77 mod va_arg;
  78 mod value;
  79
  80 #[derive(Clone)]
  81 pub struct LlvmCodegenBackend(());
  82
  83 impl ExtraBackendMethods for LlvmCodegenBackend {
  84     fn new_metadata(&self, tcx: TyCtxt<'_>, mod_name: &str) -> ModuleLlvm {
  85         ModuleLlvm::new_metadata(tcx, mod_name)
  86     }
  87
  88     fn write_compressed_metadata<'tcx>(
  89         &self,
  90         tcx: TyCtxt<'tcx>,
  91         metadata: &EncodedMetadata,
  92         llvm_module: &mut ModuleLlvm,
  93     ) {
  94         base::write_compressed_metadata(tcx, metadata, llvm_module)
  95     }
  96     fn codegen_allocator<'tcx>(
  97         &self,
  98         tcx: TyCtxt<'tcx>,
  99         mods: &mut ModuleLlvm,
 100         kind: AllocatorKind,
 101     ) {
 102         unsafe { allocator::codegen(tcx, mods, kind) }
 103     }
 104     fn compile_codegen_unit(
 105         &self,
 106         tcx: TyCtxt<'_>,
 107         cgu_name: Symbol,
 108     ) -> (ModuleCodegen<ModuleLlvm>, u64) {
 109         base::compile_codegen_unit(tcx, cgu_name)
 110     }
 111     fn target_machine_factory(
 112         &self,
 113         sess: &Session,
 114         optlvl: OptLevel,
 115         find_features: bool,
 116     ) -> Arc<dyn Fn() -> Result<&'static mut llvm::TargetMachine, String> + Send + Sync> {
 117         back::write::target_machine_factory(sess, optlvl, find_features)
 118     }
 119     fn target_cpu<'b>(&self, sess: &'b Session) -> &'b str {
 120         llvm_util::target_cpu(sess)
 121     }
 122 }
 123
 124 impl WriteBackendMethods for LlvmCodegenBackend {
 125     type Module = ModuleLlvm;
 126     type ModuleBuffer = back::lto::ModuleBuffer;
 127     type Context = llvm::Context;
 128     type TargetMachine = &'static mut llvm::TargetMachine;
 129     type ThinData = back::lto::ThinData;
 130     type ThinBuffer = back::lto::ThinBuffer;
 131     fn print_pass_timings(&self) {
 132         unsafe {
 133             llvm::LLVMRustPrintPassTimings();
 134         }
 135     }
 136     fn run_fat_lto(
 137         cgcx: &CodegenContext<Self>,
 138         modules: Vec<FatLTOInput<Self>>,
 139         cached_modules: Vec<(SerializedModule<Self::ModuleBuffer>, WorkProduct)>,
 140     ) -> Result<LtoModuleCodegen<Self>, FatalError> {
 141         back::lto::run_fat(cgcx, modules, cached_modules)
 142     }
 143     fn run_thin_lto(
 144         cgcx: &CodegenContext<Self>,
 145         modules: Vec<(String, Self::ThinBuffer)>,
 146         cached_modules: Vec<(SerializedModule<Self::ModuleBuffer>, WorkProduct)>,
 147     ) -> Result<(Vec<LtoModuleCodegen<Self>>, Vec<WorkProduct>), FatalError> {
 148         back::lto::run_thin(cgcx, modules, cached_modules)
 149     }
 150     unsafe fn optimize(
 151         cgcx: &CodegenContext<Self>,
 152         diag_handler: &Handler,
 153         module: &ModuleCodegen<Self::Module>,
 154         config: &ModuleConfig,
 155     ) -> Result<(), FatalError> {
 156         back::write::optimize(cgcx, diag_handler, module, config)
 157     }
 158     unsafe fn optimize_thin(
 159         cgcx: &CodegenContext<Self>,
 160         thin: &mut ThinModule<Self>,
 161     ) -> Result<ModuleCodegen<Self::Module>, FatalError> {
 162         back::lto::optimize_thin_module(thin, cgcx)
 163     }
 164     unsafe fn codegen(
 165         cgcx: &CodegenContext<Self>,
 166         diag_handler: &Handler,
 167         module: ModuleCodegen<Self::Module>,
 168         config: &ModuleConfig,
 169     ) -> Result<CompiledModule, FatalError> {
 170         back::write::codegen(cgcx, diag_handler, module, config)
 171     }
 172     fn prepare_thin(module: ModuleCodegen<Self::Module>) -> (String, Self::ThinBuffer) {
 173         back::lto::prepare_thin(module)
 174     }
 175     fn serialize_module(module: ModuleCodegen<Self::Module>) -> (String, Self::ModuleBuffer) {
 176         (module.name, back::lto::ModuleBuffer::new(module.module_llvm.llmod()))
 177     }
 178     fn run_lto_pass_manager(
 179         cgcx: &CodegenContext<Self>,
 180         module: &ModuleCodegen<Self::Module>,
 181         config: &ModuleConfig,
 182         thin: bool,
 183     ) {
 184         back::lto::run_pass_manager(cgcx, module, config, thin)
 185     }
 186 }
 187
 188 unsafe impl Send for LlvmCodegenBackend {} // Llvm is on a per-thread basis
 189 unsafe impl Sync for LlvmCodegenBackend {}
 190
 191 impl LlvmCodegenBackend {
 192     pub fn new() -> Box<dyn CodegenBackend> {
 193         Box::new(LlvmCodegenBackend(()))
 194     }
 195 }
 196
 197 impl CodegenBackend for LlvmCodegenBackend {
 198     fn init(&self, sess: &Session) {
 199         llvm_util::init(sess); // Make sure llvm is inited
 200     }
 201
 202     fn print(&self, req: PrintRequest, sess: &Session) {
 203         match req {
 204             PrintRequest::RelocationModels => {
 205                 println!("Available relocation models:");
 206                 for &(name, _) in back::write::RELOC_MODEL_ARGS.iter() {
 207                     println!("    {}", name);
 208                 }
 209                 println!();
 210             }
 211             PrintRequest::CodeModels => {
 212                 println!("Available code models:");
 213                 for &(name, _) in back::write::CODE_GEN_MODEL_ARGS.iter() {
 214                     println!("    {}", name);
 215                 }
 216                 println!();
 217             }
 218             PrintRequest::TlsModels => {
 219                 println!("Available TLS models:");
 220                 for &(name, _) in back::write::TLS_MODEL_ARGS.iter() {
 221                     println!("    {}", name);
 222                 }
 223                 println!();
 224             }
 225             req => llvm_util::print(req, sess),
 226         }
 227     }
 228
 229     fn print_passes(&self) {
 230         llvm_util::print_passes();
 231     }
 232
 233     fn print_version(&self) {
 234         llvm_util::print_version();
 235     }
 236
 237     fn target_features(&self, sess: &Session) -> Vec<Symbol> {
 238         target_features(sess)
 239     }
 240
 241     fn metadata_loader(&self) -> Box<MetadataLoaderDyn> {
 242         Box::new(metadata::LlvmMetadataLoader)
 243     }
 244
 245     fn provide(&self, providers: &mut ty::query::Providers<'_>) {
 246         attributes::provide(providers);
 247     }
 248
 249     fn provide_extern(&self, providers: &mut ty::query::Providers<'_>) {
 250         attributes::provide_extern(providers);
 251     }
 252
 253     fn codegen_crate<'tcx>(
 254         &self,
 255         tcx: TyCtxt<'tcx>,
 256         metadata: EncodedMetadata,
 257         need_metadata_module: bool,
 258     ) -> Box<dyn Any> {
 259         Box::new(rustc_codegen_ssa::base::codegen_crate(
 260             LlvmCodegenBackend(()),
 261             tcx,
 262             metadata,
 263             need_metadata_module,
 264         ))
 265     }
 266
 267     fn join_codegen(
 268         &self,
 269         ongoing_codegen: Box<dyn Any>,
 270         sess: &Session,
 271         dep_graph: &DepGraph,
 272     ) -> Result<Box<dyn Any>, ErrorReported> {
 273         let (codegen_results, work_products) = ongoing_codegen
 274             .downcast::<rustc_codegen_ssa::back::write::OngoingCodegen<LlvmCodegenBackend>>()
 275             .expect("Expected LlvmCodegenBackend's OngoingCodegen, found Box<Any>")
 276             .join(sess);
 277         if sess.opts.debugging_opts.incremental_info {
 278             rustc_codegen_ssa::back::write::dump_incremental_data(&codegen_results);
 279         }
 280
 281         sess.time("serialize_work_products", move || {
 282             rustc_incremental::save_work_product_index(sess, &dep_graph, work_products)
 283         });
 284
 285         sess.compile_status()?;
 286
 287         Ok(Box::new(codegen_results))
 288     }
 289
 290     fn link(
 291         &self,
 292         sess: &Session,
 293         codegen_results: Box<dyn Any>,
 294         outputs: &OutputFilenames,
 295     ) -> Result<(), ErrorReported> {
 296         let codegen_results = codegen_results
 297             .downcast::<CodegenResults>()
 298             .expect("Expected CodegenResults, found Box<Any>");
 299
 300         if sess.opts.debugging_opts.no_link {
 301             // FIXME: use a binary format to encode the `.rlink` file
 302             let rlink_data = json::encode(&codegen_results).map_err(|err| {
 303                 sess.fatal(&format!("failed to encode rlink: {}", err));
 304             })?;
 305             let rlink_file = outputs.with_extension(config::RLINK_EXT);
 306             fs::write(&rlink_file, rlink_data).map_err(|err| {
 307                 sess.fatal(&format!("failed to write file {}: {}", rlink_file.display(), err));
 308             })?;
 309             return Ok(());
 310         }
 311
 312         // Run the linker on any artifacts that resulted from the LLVM run.
 313         // This should produce either a finished executable or library.
 314         sess.time("link_crate", || {
 315             use crate::back::archive::LlvmArchiveBuilder;
 316             use rustc_codegen_ssa::back::link::link_binary;
 317
 318             let target_cpu = crate::llvm_util::target_cpu(sess);
 319             link_binary::<LlvmArchiveBuilder<'_>>(
 320                 sess,
 321                 &codegen_results,
 322                 outputs,
 323                 &codegen_results.crate_name.as_str(),
 324                 target_cpu,
 325             );
 326         });
 327
 328         // Now that we won't touch anything in the incremental compilation directory
 329         // any more, we can finalize it (which involves renaming it)
 330         rustc_incremental::finalize_session_directory(sess, codegen_results.crate_hash);
 331
 332         sess.time("llvm_dump_timing_file", || {
 333             if sess.opts.debugging_opts.llvm_time_trace {
 334                 llvm_util::time_trace_profiler_finish("llvm_timings.json");
 335             }
 336         });
 337
 338         Ok(())
 339     }
 340 }
 341
 342 pub struct ModuleLlvm {
 343     llcx: &'static mut llvm::Context,
 344     llmod_raw: *const llvm::Module,
 345     tm: &'static mut llvm::TargetMachine,
 346 }
 347
 348 unsafe impl Send for ModuleLlvm {}
 349 unsafe impl Sync for ModuleLlvm {}
 350
 351 impl ModuleLlvm {
 352     fn new(tcx: TyCtxt<'_>, mod_name: &str) -> Self {
 353         unsafe {
 354             let llcx = llvm::LLVMRustContextCreate(tcx.sess.fewer_names());
 355             let llmod_raw = context::create_module(tcx, llcx, mod_name) as *const _;
 356             ModuleLlvm { llmod_raw, llcx, tm: create_target_machine(tcx, false) }
 357         }
 358     }
 359
 360     fn new_metadata(tcx: TyCtxt<'_>, mod_name: &str) -> Self {
 361         unsafe {
 362             let llcx = llvm::LLVMRustContextCreate(tcx.sess.fewer_names());
 363             let llmod_raw = context::create_module(tcx, llcx, mod_name) as *const _;
 364             ModuleLlvm {
 365                 llmod_raw,
 366                 llcx,
 367                 tm: create_informational_target_machine(&tcx.sess, false),
 368             }
 369         }
 370     }
 371
 372     fn parse(
 373         cgcx: &CodegenContext<LlvmCodegenBackend>,
 374         name: &CStr,
 375         buffer: &[u8],
 376         handler: &Handler,
 377     ) -> Result<Self, FatalError> {
 378         unsafe {
 379             let llcx = llvm::LLVMRustContextCreate(cgcx.fewer_names);
 380             let llmod_raw = back::lto::parse_module(llcx, name, buffer, handler)?;
 381             let tm = match (cgcx.tm_factory.0)() {
 382                 Ok(m) => m,
 383                 Err(e) => {
 384                     handler.struct_err(&e).emit();
 385                     return Err(FatalError);
 386                 }
 387             };
 388
 389             Ok(ModuleLlvm { llmod_raw, llcx, tm })
 390         }
 391     }
 392
 393     fn llmod(&self) -> &llvm::Module {
 394         unsafe { &*self.llmod_raw }
 395     }
 396 }
 397
 398 impl Drop for ModuleLlvm {
 399     fn drop(&mut self) {
 400         unsafe {
 401             llvm::LLVMContextDispose(&mut *(self.llcx as *mut _));
 402             llvm::LLVMRustDisposeTargetMachine(&mut *(self.tm as *mut _));
 403         }
 404     }
 405 }